I grew up in the 50s and 60s. There was certainly less variety in food, especially in fresh vegetables, where many things you find routinely today you just couldn’t get (e.g., kale, avocado, grape tomatoes, jalapenos) or could only get in season.
Dishes were simpler,* without fancy sauces (or even white sauce, which I never heard about until the mid-70s). That doesn’t make it bad; it meant it depended on the skill of the cook.
And my mother was a pretty good cook (as was her mother). Some of my favorites from that era were:
Corn flake chicken (note who I linked to) where the chicken was dredged in crushed corn flakes and baked.
Chicken Kiev.
London broil (note: the cuts labeled “London broil” in the supermarket these days are not right for London broil, which is made from flank steak). Marinated flank steak put under a broiler just long enough to crisp the top (and flipped to repeat that on the other side). The interior is blood rare, and you have to cut it on an angle across the fibers. The result is thin, tender, crispy on the outside, and delicious.
Fried liver. I know this isn’t for anyone, but it’s delicious and certainly my favorite meal. You dredge beef liver in breadcrumbs, then fry it in butter for 2-3 minutes a side (add more butter when you flip it). The interior should have a tinge of pink when served. I once made it for someone who hated liver and she admitted it tasted pretty good.
She also made an excellent meat loaf, too.
We lived on Long Island, so seafood – clams and scallops – were often on the menu for special occasions. Sometimes we’d cook fish we caught (my favorite was blowfish – a cousin of fugu).
When fresh vegetables were in season, we’d have them. Otherwise, we used frozen (never canned). We did make salads from the things we could get – iceberg lettuce, cucumber, tomato, celery, carrots. I preferred Russian and Catalina dressing, which was uncommon (Italian was the most popular at the time).
Potatoes were a part of each meal, usually baked (my favorite – we would hollow them out and then eat the skins with butter. Mmmmmm.).
I don’t recall her ever making fried chicken. Or a casserole. She cooked vegetables – fresh or frozen – just long enough to heat them up; often they were put on the stove just before she took the main course out of the oven.
Today, of course, we have far more options, far more recipes, and due to the Internet, better access to recipes. But it’s untrue that there wasn’t good food in that era – there were just bad cooks.
*Julia Child had trouble finding a publisher for her Mastering the Art of French Cooking because people believe that home cooks weren’t interest in fancy dishes that too a lot of time to prepare.